| 1. |
- Wagner, J., et al.
(författare)
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First 230? : GHz VLBI fringes on 3C 279 using the APEX Telescope (Research Note)
- 2015
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 581
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Tidskriftsartikel (refereegranskat)abstract
- Aims. We report about a 230? GHz very long baseline interferometry (VLBI) fringe finder observation of blazar 3C 279 with the APEX telescope in Chile, the phased submillimeter array (SMA), and the SMT of the Arizona Radio Observatory (ARO). Methods. We installed VLBI equipment and measured the APEX station position to 1? cm accuracy (1σ). We then observed 3C 279 on 2012 May 7 in a 5? h 230? GHz VLBI track with baseline lengths of 2800? Mλ to 7200? Mλ and a finest fringe spacing of 28.6? μas. Results. Fringes were detected on all baselines with signal-to-noise ratios of 12 to 55 in 420? s. The correlated flux density on the longest baseline was ∼0.3? Jy beam-1, out of a total flux density of 19.8? Jy. Visibility data suggest an emission region ≤ 38? μas in size, and at least two components, possibly polarized. We find a lower limit of the brightness temperature of the inner jet region of about 1010? K. Lastly, we find an upper limit of 20% on the linear polarization fraction at a fringe spacing of ∼ 38? μas. Conclusions. With APEX the angular resolution of 230? GHz VLBI improves to 28.6? μas. This allows one to resolve the last-photon ring around the Galactic Center black hole event horizon, expected to be 40? μas in diameter, and probe radio jet launching at unprecedented resolution, down to a few gravitational radii in galaxies like M 87. To probe the structure in the inner parsecs of 3C 279 in detail, follow-up observations with APEX and five other mm-VLBI stations have been conducted (March 2013) and are being analyzed.
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| 2. |
- Goidanich, S., et al.
(författare)
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Effect of the environment on the metal release and corrosion behaviour of different copper-based alloys : Field exposures at 5 different test sites in Europe
- 2008
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Ingår i: 17th International Corrosion Congress 2008. - 9781615674251 ; , s. 102-115
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Konferensbidrag (refereegranskat)abstract
- Diffuse emissions and dispersion of metals from different sources in the society have lately received an increased concern from an environmental perspective. Large research efforts have been initiated and undertaken by the division of Corrosion Science at KTH to fill knowledge gaps on corrosion-induced metal release from external constructions and buildings. The generation of such data is of paramount importance for the on-going assessment of flows and potential adverse environmental effects caused by released metals. Generated information is also essential for an improved understanding of prevailing atmospheric corrosion processes of importance for the preservation of our cultural heritage, e.g. bronze statues exposed to the atmosphere. This paper summarizes and compares long-term metal release data from pure copper, bronze (6%wt Sn) and brass (20%wt Zn) exposed at unsheltered conditions in five European environments of significantly different climatic and pollutant conditions; three urban sites (Stockholm-Sweden, Milan-Italy and Madrid-Spain) and two marine sites (Brest-France, Cadiz-Spain). Generated data are interpreted with respect to parallel multi-analytical studies of changes in patina characteristics, corrosion rates and differences in prevailing environmental conditions.
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| 3. |
- Gómez, M., et al.
(författare)
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From agroindustries to integrated biomass logistics centres. Agroinlog project : Summary of final results
- 2020
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Ingår i: European Biomass Conference and Exhibition Proceedings. - : ETA-Florence Renewable Energies. ; , s. 941-952
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Konferensbidrag (refereegranskat)abstract
- AGROinLOG project has tested the integrated biomass logistics centres (IBLC) concept in three real agro-industries in Europe. The relevance of the IBLC strategy relies on the fact that it allows agro-industries to create a new activity with lower investment, increasing incomes, stabilizing their annual activity (avoiding idle periods) and maintaining or creating new jobs. The demos’ studies were performed in Spain at a fodder industry, in Greece at an olive oil industry, and in Sweden inside a cereal processing industry. AGROinLOG validated these demos´ business models from a holistic perspective, also studying the replicability of the IBLC business model in other agro-industries from different sectors (vegetable oil extraction, olive oil chain, feed & fodder, wine, grain chain and sugar industry). Sectorial analysis was carried out as well, allowing the identification of opportunities among the targeted sector to replicate the IBLC concept, drawing barriers to overcome in each case. Thus, technical, economic and environmental feasibility of integrated biomass logistics centers (IBLCs) for food and non-food products have been assessed in detail.
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| 4. |
- Lopez-Sanchez, Patricia, et al.
(författare)
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Nanostructure and poroviscoelasticity in cell wall materials from onion, carrot and apple : Roles of pectin
- 2020
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Ingår i: Food Hydrocolloids. - : Elsevier B.V.. - 0268-005X .- 1873-7137. ; 98
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Tidskriftsartikel (refereegranskat)abstract
- The hierarchical organisation of polysaccharides in primary plant cell walls is responsible for their unique mechanical properties, and in turn for the textural and rheological properties of plant-based foods and ingredients. It is expected that at the nano scale, the mechanical properties of cell wall materials arise from a combination of structural deformation of the polysaccharide networks and hydraulic properties of the continuous water phase, as has been shown for other cellulose-based composites. Pectin plays a key role in the load bearing properties of (bacterial) cellulose-pectin composites due to its contribution to both hydration structure and the dynamics of water movement. To investigate whether these features are also important in plant cell wall materials we have used a set of advanced characterisation techniques to elucidate cell wall structural features at different length scales (X-ray diffraction and small angle X-ray and neutron scattering) in cell walls from two dicotyledons (apple and carrot) and a non-commelinid monocotyledon (onion). The strength of isolated cell walls was measured under compression and fitted to a poroviscoelastic mechanical model, demonstrating that the mechanical properties of the isolated cell wall materials are directly linked to both polysaccharide networks and fluid flow through the networks. Our results show how pectin polysaccharides influence the viscoelastic behaviour of these materials and contribute to the texture of plant-derived food systems.
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| 5. |
- Chang, Tingru, et al.
(författare)
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The role of Sn on the long-term atmospheric corrosion of binary Cu-Sn bronze alloys in architecture
- 2019
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Ingår i: Corrosion Science. - : Elsevier Ltd. - 0010-938X .- 1879-0496. ; 149, s. 54-67
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Tidskriftsartikel (refereegranskat)abstract
- The role of Sn on the atmospheric corrosion performance of binary Cu-Sn bronze alloys (4–6 wt.% Sn) compared with Cu metal used in outdoor architecture is elucidated in terms of microstructure, native surface oxide composition, patina evolution, corrosion rates, appearance and metal release. Results are presented for non-exposed surfaces and surfaces exposed at different urban and marine sites in Europe up to 5 years and based on multi-analytical findings from microscopic, spectroscopic, electrochemical and chemical investigations. Alloying influenced the corrosion, aesthetic appearance and patina evolution, differently for urban and marine sites, whereas no effects were observed on the release pattern. © 2019 The Authors
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| 6. |
- Fernández, A., et al.
(författare)
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Effects of ionizing radiation in ethylene-vinyl alcohol copolymers and in composites containing microfibrillated cellulose
- 2008
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Ingår i: Journal of Applied Polymer Science. - : Wiley. - 0021-8995 .- 1097-4628. ; 109:1, s. 126-134
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Tidskriftsartikel (refereegranskat)abstract
- This study reports on the effect of gamma radiation on morphological, thermal, and water barrier properties of pure ethylene vinyl alcohol copolymers (EVOH29 and EVOH44) and its biocomposites with the nanofiller microfibrillated cellulose (2 wt%). Added microfibrillated cellulose (MFC) preserved the transparency of EVOH films but led to a decrease in water barrier properties. Gamma irradiation at low (30 kGy) and high doses (60 kGy) caused some irreversible changes in the phase morphology of EVOH29 and EVOH44 copolymers that could be associated to crosslinking and other chemical alterations. Additionally, the EVOH copolymers and the EVOH composites reduced the number of hygroscopic hydroxyl functionalities during the irradiation processing and novel carbonyl based chemistry was, in turn, detected. As a result of the above alterations, the water barrier properties of both neat materials and composites irradiated at low doses were notably enhanced, counteracting the detrimental effect on water barrier of adding MFC to the EVOH matrix. © 2008 Wiley Periodicals, Inc.
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| 7. |
- Holmgren, Jan, 1944, et al.
(författare)
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Mucosal adjuvants and anti-infection and anti-immunopathology vaccines based on cholera toxin, cholera toxin B subunit and CpG DNA
- 2005
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Ingår i: Immunology Letters. - : Elsevier. - 0165-2478 .- 1879-0542. ; 97:2, s. 181-8
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Tidskriftsartikel (refereegranskat)abstract
- Mucosal immunisation may be used both to protect the mucosal surfaces against infections and as a means for immunological treatment of peripheral immunopathological disorders through the induction of systemic antigen-specific tolerance ('oral tolerance'). The development of mucosal vaccines, whether for prevention of infectious diseases or for oral tolerance immunotherapy, requires efficient antigen delivery and adjuvant systems that can help to present the appropriate vaccine or immunotherapy antigens to the mucosal immune system. The most potent (but also toxic) mucosal adjuvants are cholera toxin (CT) and the closely related Escherichia coli heat-labile enterotoxin (LT), and much effort and significant progress have been made recently to generate toxicologically acceptable derivatives of these toxins with retained adjuvant activity. Among these are the non-toxic, recombinantly produced cholera toxin B-subunit (CTB). CTB is a specific protective antigen component of a widely registered oral cholera vaccine as well as a promising vector for either giving rise to mucosal anti-infective immunity or for inducing peripheral anti-inflammatory tolerance to chemically or genetically linked foreign antigens administered mucosally. CT and CTB have also recently been used as combined vectors and adjuvants for markedly promoting ex vivo dendritic cell (DC) vaccination with different antigens and also steering the immune response to the in vivo-reinfused DCs towards either broad Th1 + Th2 + CTL immunity (CT) or Th2 or tolerance (CTB). Another type of mucosal adjuvants is represented by bacterial DNA or synthetic oligodeoxynucleotides containing CpG-motifs, which especially when linked to CTB have been found to effectively stimulate both innate and adaptive mucosal immune responses. The properties and clinical potential of these different classes of adjuvants are being discussed. © 2004 Elsevier B.V. All rights reserved.
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| 8. |
- Gracia-Marco, Luis A., et al.
(författare)
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Seasonal variation in physical activity and sedentary time in different European regions. The HELENA study
- 2013
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Ingår i: Journal of Sports Sciences. - : Routledge. - 0264-0414 .- 1466-447X. ; 31:16, s. 1831-1840
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Tidskriftsartikel (refereegranskat)abstract
- This report aims (1) to examine the association between seasonality and physical activity (PA) and sedentary time in European adolescents and (2) to investigate whether this association was influenced by geographical location (Central-North versus South of Europe), which implies more or less extreme weather and daylight hours. Valid data on PA, sedentary time and seasonality were obtained in 2173 adolescents (1175 females; 12.5-17.5 years) included in this study. Physical activity and sedentary time were measured by accelerometers. ANCOVA was conducted to analyse the differences in PA and sedentary time across seasons. Results showed that girls had lower levels of moderate to vigorous PA (MVPA) and average PA, and spent more time in sedentary activities in winter compared with spring (all P < 0.05). Stratified analyses showed differences in PA and sedentary time between winter and spring in European girls from Central-North of Europe (P < 0.05 for sedentary time). There were no differences between PA and sedentary time across seasonality in boys. In conclusion, winter is related with less time spent in MVPA, lower average PA and higher time spent in sedentary activities in European adolescent girls, compared with spring. These differences seem to mainly occur in Central-North Europe.
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